Ordinal.exists_ord_cof_eq

∀ (α : Type u) [inst : LinearOrder α] [inst_1 : WellFoundedLT α],
  ∃ s, IsCofinal s ∧ (Ordinal.type fun x1 x2 => x1 < x2) = (Order.cof α).ord

Every well-order has a cofinal subset of order type (cof α).ord.

Defined in: Mathlib.SetTheory.Cardinal.Cofinality.Ordinal
Cited by: 5 results in Mathlib
Foundations: Depth 80 from the axioms · uses propext, Classical.choice, Quot.sound
Assumes: LinearOrder WellFoundedLT

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